P726 Cardiac amyloidosis: unmasking the simulator

Abstract

Abstract Introduction A non-invasive diagnosis of cardiac amyloidosis is a challenge, especially in cases of atypical phenotypic presentation. Differential diagnosis includes hypertrophic cardiomyopathy (HCM), hypertensive cardiomyopathy, and other infiltrative disorders. Multimodality imaging is essential to make a final diagnosis. Case We present the case of a 65 years old woman, with a personal history of resistant arterial hypertension and mild hypertensive cardiomyopathy. She was diagnosed 6 years earlier with multiple myeloma, treated with chemotherapy and allogeneic hematopoietic stem cell transplant, presenting with several relapses and in a stable situation at the moment of our first consult. The patient was referred for heart failure in context of acquired community pneumonia one month earlier. Transthoracic echocardiography showed severe asymmetric left ventricle (LV) hypertrophy (Image A), systolic anterior motion of the mitral valve and diastolic dysfunction suggestive of HCM, not present in the previous examination. Strain imaging of the LV showed a typical amyloid infiltration pattern, with lower longitudinal strain values in the base compared to the apical segments (Image D). Further characterization of the myocardial tissue established the diagnosis along with performing a cardiac magnetic nuclear imaging (MRI). It showed the presence of inferior septum severe LV hypertrophy along with extensive patchy late gadolinium enhancement (LGE) of the lateral wall involving the endocardium (Image C), with normal LV contractility. There was no pleural effusion, but a small pericardial effusion was seen (Image B). With the suspicion of infiltrative heart disease, probably amyloid with an atypical LGE pattern, an oral mucosal biopsy was performed confirming amyloid diagnosis (Images E1,E2). Heart failure treatment was continued, but clinical evolution was poor with the deceasement of the patient 3 years after diagnosis. Discussion This case represents an example of the variety of imaging patterns we can see in cardiac amyloidosis. Despite the classical pattern of cardiac amyloidosis, with concentric LV hypertrophy, up to 8% of cases may present with asymmetrical LV hypertrophy, mimicking HCM. LGE extension and pattern can shows this variability as well: global transmural or subendocardial LGE is the most common, but focal patterns (up to 6% of cases) are described. The complexity of the diagnosis in these cases require a clinical and multimodality image approach. Abstract P726 Figure. Images of the case